Establishment and Application of PCR Combined with Dot Blot Hybridization for Detecting Avian Polyomavirus
Budgerigar fledgling disease(BFD)is an acute viral infectious disease caused by avian polyomavirus(APV),which could lead to death of various parrot nestlings and seriously endanger the healthy development of parrot industry. In order to improve the sensitivity and specificity of molecular biological methods to detect APV,the APV gene fragment was cloned and sequenced. After designing and synthesizing a pair of specific primers as well as carrying out PCR amplification,gene fragment with the nucleotide length of 731 bp was obtained by taking VP1 gene as a template,and then the fragment was marked with DIG to prepare a specific probe for detecting APV;the sensitivity of the probe was detected and compared with general PCR;other 7 kinds of isolated and prepared virus nucleic acids were used to evaluate the specificity of the probe;the lesions of parrots suspected to be infected with APV were detected by dot blot hybridization using the probe,and the whole genome sequences of the positive APV were amplified and analyzed. The results showed that the probe could detect 2 pg of APV specific nucleic acid fragment;and only the positive nucleic acids of APV-VP1 showed positive reaction,while the negative one and other 7 kinds of virus nucleic acids all showed negative reaction. In conclusion,the established method could be used for clinical preliminary diagnosis due to its high sensitivity and specificity. Therefore,molecular epidemiological investigation and clinical diagnosis of APV infection in China were provided with technical supports by the established method.